Really tightly crafted and structured, like a piece of classical music. Aside from the fact that it was good, compelling reading, the whole infrastructure of it was interesting to follow. With, yes, a major deus ex machina, but Phillips isn't asking us to believe he was anything other than that, so it managed not to grate. Plus he had his counterpart - all characters were carefully but not heavy-handedly twinned - so there was a place for him. And the language was terrific. She's so controlled.